xref: /openbmc/qemu/hw/i386/microvm-dt.c (revision b21e2380)
1 /*
2  * microvm device tree support
3  *
4  * This generates an device tree for microvm and exports it via fw_cfg
5  * as "etc/fdt" to the firmware (edk2 specifically).
6  *
7  * The use case is to allow edk2 find the pcie ecam and the virtio
8  * devices, without adding an ACPI parser, reusing the fdt parser
9  * which is needed anyway for the arm platform.
10  *
11  * Note 1: The device tree is incomplete. CPUs and memory is missing
12  *         for example, those can be detected using other fw_cfg files.
13  *         Also pci ecam irq routing is not there, edk2 doesn't use
14  *         interrupts.
15  *
16  * Note 2: This is for firmware only. OSes should use the more
17  *         complete ACPI tables for hardware discovery.
18  *
19  * ----------------------------------------------------------------------
20  *
21  * This program is free software; you can redistribute it and/or modify it
22  * under the terms and conditions of the GNU General Public License,
23  * version 2 or later, as published by the Free Software Foundation.
24  *
25  * This program is distributed in the hope it will be useful, but WITHOUT
26  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
27  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
28  * more details.
29  *
30  * You should have received a copy of the GNU General Public License along with
31  * this program.  If not, see <http://www.gnu.org/licenses/>.
32  */
33 #include "qemu/osdep.h"
34 #include "qemu/cutils.h"
35 #include "sysemu/device_tree.h"
36 #include "hw/char/serial.h"
37 #include "hw/i386/fw_cfg.h"
38 #include "hw/rtc/mc146818rtc.h"
39 #include "hw/sysbus.h"
40 #include "hw/virtio/virtio-mmio.h"
41 #include "hw/usb/xhci.h"
42 
43 #include "microvm-dt.h"
44 
45 static bool debug;
46 
47 static void dt_add_microvm_irq(MicrovmMachineState *mms,
48                                const char *nodename, uint32_t irq)
49 {
50     int index = 0;
51 
52     if (irq >= IO_APIC_SECONDARY_IRQBASE) {
53         irq -= IO_APIC_SECONDARY_IRQBASE;
54         index++;
55     }
56 
57     qemu_fdt_setprop_cell(mms->fdt, nodename, "interrupt-parent",
58                           mms->ioapic_phandle[index]);
59     qemu_fdt_setprop_cells(mms->fdt, nodename, "interrupts", irq, 0);
60 }
61 
62 static void dt_add_virtio(MicrovmMachineState *mms, VirtIOMMIOProxy *mmio)
63 {
64     SysBusDevice *dev = SYS_BUS_DEVICE(mmio);
65     VirtioBusState *mmio_virtio_bus = &mmio->bus;
66     BusState *mmio_bus = &mmio_virtio_bus->parent_obj;
67     char *nodename;
68 
69     if (QTAILQ_EMPTY(&mmio_bus->children)) {
70         return;
71     }
72 
73     hwaddr base = dev->mmio[0].addr;
74     hwaddr size = 512;
75     unsigned index = (base - VIRTIO_MMIO_BASE) / size;
76     uint32_t irq = mms->virtio_irq_base + index;
77 
78     nodename = g_strdup_printf("/virtio_mmio@%" PRIx64, base);
79     qemu_fdt_add_subnode(mms->fdt, nodename);
80     qemu_fdt_setprop_string(mms->fdt, nodename, "compatible", "virtio,mmio");
81     qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "reg", 2, base, 2, size);
82     qemu_fdt_setprop(mms->fdt, nodename, "dma-coherent", NULL, 0);
83     dt_add_microvm_irq(mms, nodename, irq);
84     g_free(nodename);
85 }
86 
87 static void dt_add_xhci(MicrovmMachineState *mms)
88 {
89     const char compat[] = "generic-xhci";
90     uint32_t irq = MICROVM_XHCI_IRQ;
91     hwaddr base = MICROVM_XHCI_BASE;
92     hwaddr size = XHCI_LEN_REGS;
93     char *nodename;
94 
95     nodename = g_strdup_printf("/usb@%" PRIx64, base);
96     qemu_fdt_add_subnode(mms->fdt, nodename);
97     qemu_fdt_setprop(mms->fdt, nodename, "compatible", compat, sizeof(compat));
98     qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "reg", 2, base, 2, size);
99     qemu_fdt_setprop(mms->fdt, nodename, "dma-coherent", NULL, 0);
100     dt_add_microvm_irq(mms, nodename, irq);
101     g_free(nodename);
102 }
103 
104 static void dt_add_pcie(MicrovmMachineState *mms)
105 {
106     hwaddr base = PCIE_MMIO_BASE;
107     int nr_pcie_buses;
108     char *nodename;
109 
110     nodename = g_strdup_printf("/pcie@%" PRIx64, base);
111     qemu_fdt_add_subnode(mms->fdt, nodename);
112     qemu_fdt_setprop_string(mms->fdt, nodename,
113                             "compatible", "pci-host-ecam-generic");
114     qemu_fdt_setprop_string(mms->fdt, nodename, "device_type", "pci");
115     qemu_fdt_setprop_cell(mms->fdt, nodename, "#address-cells", 3);
116     qemu_fdt_setprop_cell(mms->fdt, nodename, "#size-cells", 2);
117     qemu_fdt_setprop_cell(mms->fdt, nodename, "linux,pci-domain", 0);
118     qemu_fdt_setprop(mms->fdt, nodename, "dma-coherent", NULL, 0);
119 
120     qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "reg",
121                                  2, PCIE_ECAM_BASE, 2, PCIE_ECAM_SIZE);
122     if (mms->gpex.mmio64.size) {
123         qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "ranges",
124 
125                                      1, FDT_PCI_RANGE_MMIO,
126                                      2, mms->gpex.mmio32.base,
127                                      2, mms->gpex.mmio32.base,
128                                      2, mms->gpex.mmio32.size,
129 
130                                      1, FDT_PCI_RANGE_MMIO_64BIT,
131                                      2, mms->gpex.mmio64.base,
132                                      2, mms->gpex.mmio64.base,
133                                      2, mms->gpex.mmio64.size);
134     } else {
135         qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "ranges",
136 
137                                      1, FDT_PCI_RANGE_MMIO,
138                                      2, mms->gpex.mmio32.base,
139                                      2, mms->gpex.mmio32.base,
140                                      2, mms->gpex.mmio32.size);
141     }
142 
143     nr_pcie_buses = PCIE_ECAM_SIZE / PCIE_MMCFG_SIZE_MIN;
144     qemu_fdt_setprop_cells(mms->fdt, nodename, "bus-range", 0,
145                            nr_pcie_buses - 1);
146 
147     g_free(nodename);
148 }
149 
150 static void dt_add_ioapic(MicrovmMachineState *mms, SysBusDevice *dev)
151 {
152     hwaddr base = dev->mmio[0].addr;
153     char *nodename;
154     uint32_t ph;
155     int index;
156 
157     switch (base) {
158     case IO_APIC_DEFAULT_ADDRESS:
159         index = 0;
160         break;
161     case IO_APIC_SECONDARY_ADDRESS:
162         index = 1;
163         break;
164     default:
165         fprintf(stderr, "unknown ioapic @ %" PRIx64 "\n", base);
166         return;
167     }
168 
169     nodename = g_strdup_printf("/ioapic%d@%" PRIx64, index + 1, base);
170     qemu_fdt_add_subnode(mms->fdt, nodename);
171     qemu_fdt_setprop_string(mms->fdt, nodename,
172                             "compatible", "intel,ce4100-ioapic");
173     qemu_fdt_setprop(mms->fdt, nodename, "interrupt-controller", NULL, 0);
174     qemu_fdt_setprop_cell(mms->fdt, nodename, "#interrupt-cells", 0x2);
175     qemu_fdt_setprop_cell(mms->fdt, nodename, "#address-cells", 0x2);
176     qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "reg",
177                                  2, base, 2, 0x1000);
178 
179     ph = qemu_fdt_alloc_phandle(mms->fdt);
180     qemu_fdt_setprop_cell(mms->fdt, nodename, "phandle", ph);
181     qemu_fdt_setprop_cell(mms->fdt, nodename, "linux,phandle", ph);
182     mms->ioapic_phandle[index] = ph;
183 
184     g_free(nodename);
185 }
186 
187 static void dt_add_isa_serial(MicrovmMachineState *mms, ISADevice *dev)
188 {
189     const char compat[] = "ns16550";
190     uint32_t irq = object_property_get_int(OBJECT(dev), "irq", NULL);
191     hwaddr base = object_property_get_int(OBJECT(dev), "iobase", NULL);
192     hwaddr size = 8;
193     char *nodename;
194 
195     nodename = g_strdup_printf("/serial@%" PRIx64, base);
196     qemu_fdt_add_subnode(mms->fdt, nodename);
197     qemu_fdt_setprop(mms->fdt, nodename, "compatible", compat, sizeof(compat));
198     qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "reg", 2, base, 2, size);
199     dt_add_microvm_irq(mms, nodename, irq);
200 
201     if (base == 0x3f8 /* com1 */) {
202         qemu_fdt_setprop_string(mms->fdt, "/chosen", "stdout-path", nodename);
203     }
204 
205     g_free(nodename);
206 }
207 
208 static void dt_add_isa_rtc(MicrovmMachineState *mms, ISADevice *dev)
209 {
210     const char compat[] = "motorola,mc146818";
211     uint32_t irq = RTC_ISA_IRQ;
212     hwaddr base = RTC_ISA_BASE;
213     hwaddr size = 8;
214     char *nodename;
215 
216     nodename = g_strdup_printf("/rtc@%" PRIx64, base);
217     qemu_fdt_add_subnode(mms->fdt, nodename);
218     qemu_fdt_setprop(mms->fdt, nodename, "compatible", compat, sizeof(compat));
219     qemu_fdt_setprop_sized_cells(mms->fdt, nodename, "reg", 2, base, 2, size);
220     dt_add_microvm_irq(mms, nodename, irq);
221     g_free(nodename);
222 }
223 
224 static void dt_setup_isa_bus(MicrovmMachineState *mms, DeviceState *bridge)
225 {
226     BusState *bus = qdev_get_child_bus(bridge, "isa.0");
227     BusChild *kid;
228     Object *obj;
229 
230     QTAILQ_FOREACH(kid, &bus->children, sibling) {
231         DeviceState *dev = kid->child;
232 
233         /* serial */
234         obj = object_dynamic_cast(OBJECT(dev), TYPE_ISA_SERIAL);
235         if (obj) {
236             dt_add_isa_serial(mms, ISA_DEVICE(obj));
237             continue;
238         }
239 
240         /* rtc */
241         obj = object_dynamic_cast(OBJECT(dev), TYPE_MC146818_RTC);
242         if (obj) {
243             dt_add_isa_rtc(mms, ISA_DEVICE(obj));
244             continue;
245         }
246 
247         if (debug) {
248             fprintf(stderr, "%s: unhandled: %s\n", __func__,
249                     object_get_typename(OBJECT(dev)));
250         }
251     }
252 }
253 
254 static void dt_setup_sys_bus(MicrovmMachineState *mms)
255 {
256     BusState *bus;
257     BusChild *kid;
258     Object *obj;
259 
260     /* sysbus devices */
261     bus = sysbus_get_default();
262     QTAILQ_FOREACH(kid, &bus->children, sibling) {
263         DeviceState *dev = kid->child;
264 
265         /* ioapic */
266         obj = object_dynamic_cast(OBJECT(dev), TYPE_IOAPIC);
267         if (obj) {
268             dt_add_ioapic(mms, SYS_BUS_DEVICE(obj));
269             continue;
270         }
271     }
272 
273     QTAILQ_FOREACH(kid, &bus->children, sibling) {
274         DeviceState *dev = kid->child;
275 
276         /* virtio */
277         obj = object_dynamic_cast(OBJECT(dev), TYPE_VIRTIO_MMIO);
278         if (obj) {
279             dt_add_virtio(mms, VIRTIO_MMIO(obj));
280             continue;
281         }
282 
283         /* xhci */
284         obj = object_dynamic_cast(OBJECT(dev), TYPE_XHCI_SYSBUS);
285         if (obj) {
286             dt_add_xhci(mms);
287             continue;
288         }
289 
290         /* pcie */
291         obj = object_dynamic_cast(OBJECT(dev), TYPE_GPEX_HOST);
292         if (obj) {
293             dt_add_pcie(mms);
294             continue;
295         }
296 
297         /* isa */
298         obj = object_dynamic_cast(OBJECT(dev), "isabus-bridge");
299         if (obj) {
300             dt_setup_isa_bus(mms, DEVICE(obj));
301             continue;
302         }
303 
304         if (debug) {
305             obj = object_dynamic_cast(OBJECT(dev), TYPE_IOAPIC);
306             if (obj) {
307                 /* ioapic already added in first pass */
308                 continue;
309             }
310             fprintf(stderr, "%s: unhandled: %s\n", __func__,
311                     object_get_typename(OBJECT(dev)));
312         }
313     }
314 }
315 
316 void dt_setup_microvm(MicrovmMachineState *mms)
317 {
318     X86MachineState *x86ms = X86_MACHINE(mms);
319     int size = 0;
320 
321     mms->fdt = create_device_tree(&size);
322 
323     /* root node */
324     qemu_fdt_setprop_string(mms->fdt, "/", "compatible", "linux,microvm");
325     qemu_fdt_setprop_cell(mms->fdt, "/", "#address-cells", 0x2);
326     qemu_fdt_setprop_cell(mms->fdt, "/", "#size-cells", 0x2);
327 
328     qemu_fdt_add_subnode(mms->fdt, "/chosen");
329     dt_setup_sys_bus(mms);
330 
331     /* add to fw_cfg */
332     if (debug) {
333         fprintf(stderr, "%s: add etc/fdt to fw_cfg\n", __func__);
334     }
335     fw_cfg_add_file(x86ms->fw_cfg, "etc/fdt", mms->fdt, size);
336 
337     if (debug) {
338         fprintf(stderr, "%s: writing microvm.fdt\n", __func__);
339         if (!g_file_set_contents("microvm.fdt", mms->fdt, size, NULL)) {
340             fprintf(stderr, "%s: writing microvm.fdt failed\n", __func__);
341             return;
342         }
343         int ret = system("dtc -I dtb -O dts microvm.fdt");
344         if (ret != 0) {
345             fprintf(stderr, "%s: oops, dtc not installed?\n", __func__);
346         }
347     }
348 }
349